From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932564AbZDIKcC (ORCPT ); Thu, 9 Apr 2009 06:32:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932985AbZDIKba (ORCPT ); Thu, 9 Apr 2009 06:31:30 -0400 Received: from one.firstfloor.org ([213.235.205.2]:43615 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760912AbZDIKb3 (ORCPT ); Thu, 9 Apr 2009 06:31:29 -0400 To: Imre Gergely Cc: linux-kernel@vger.kernel.org Subject: Re: Finding lost memory + kernel messages explained From: Andi Kleen References: <49DDB609.8050405@narancs.net> Date: Thu, 09 Apr 2009 12:31:27 +0200 In-Reply-To: <49DDB609.8050405@narancs.net> (Imre Gergely's message of "Thu, 09 Apr 2009 11:47:05 +0300") Message-ID: <87y6ua86f4.fsf@basil.nowhere.org> User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/22.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Imre Gergely writes: > > That would be around 3896MB. My question is: where does the memory go? > Is it normal to 'lose' that much (~130MB) ? I wrote a paper about this topic some time ago. http://halobates.de/memory.pdf http://halobates.de/memorywaste.pdf > One thing I tried was appending iommu=off at boot, which gave me back That means if you have any devices that cannot addresses > 32bit they will panic with that setting. -Andi -- ak@linux.intel.com -- Speaking for myself only.